Etching machine and paddle element therefor



C. S. MARTZ March 28, 1961 ETCHING MACHINE AND PADDLE ELEMENT THEREFOR Filed March 24, 1958 3 Sheets-Sheet 1 F IG.

ATTORNEYS C. S. MARTZ March 28, 1961 ETCHING MACHINE AND PADDLE ELEMENT THEREFOR Filed March 24, 1958 3 Sheets-Sheet 2 FIG.

INVENTOR.

CHARLES S. MARTZ ao-k4. WM

ATTORNEYS March 28, 1961 c, s, MARTZ 2,976,635

ETCHING MACHINE AND PADDLE ELEMENT THEREFOR Filed March 24, 1958 5 Sheets-Sheet 3 INVENTOR. CHARLES S. MARTZ 804% MEMM ATTORNEYS United States Patent Charles S. Martz, Aurora, Mo., assignor to The Tasope Company, Aurora, Mo., a firm or partnership Filed Mar. 24, 1958 Ser. No. 723,532 10 Claims. 41-9) This invention relates to improvements in an etching machine.

It is a major objective of the present improvements to provide a paddle construction particularly adapted for use in an etching machine which realizes a more effective and efiicient distribution of the etchant on the work piece.

An important objective is achieved by the provision of an air agitator for the supply of etchant in the tank which operates to raise the etchant level so that particular paddle portions will effectively contact and hold etchant upon operation of the paddle. Another important object is realized by the construction and disposition of the etchant tank so that a minimal quantity of etchant can be used, thus resulting in considerable economies because the etchant is easily contaminated and requires replacement at frequent intervals. 'j Yet another important object is provided by an improved tank construction and cooperating apparatus for cooling the etchant during the etching process.

Still another important object is achieved by the provision of an etching machine that is durable in construction, and economical and efiicient in operation.

The foregoing and numerous other objects and advantages of the invention will more clearly appear from the following detailed description of a preferred embodiment, particularly when considered in connection with the accompanying drawings, in which:

' Fig. 1 is a perspective view of the etching machine with the lid in an opened position;

Fig. 2 is a side elevational view of the etching machine showing 'various parts broken away to more'clearly illustrate the paddle drive, the cooling mechanism, and the work-supporting and -rotating mechanism;

Fig. 3 is a cross sectional view of the machine as seen along staggered line 33 of Fig. 2;

Fig. 4 is a rear elevational view of the etching machine;

Fig. 5 is an enlarged cross sectional view of the paddle as seen along line 55 of Fig. 3, and

Fig. 6 is a perspective view of one paddle with connected gussets. Referring now by characters of reference to the drawings, it is seen that the tank generally indicated at 10 is a box-like structure including angularly related bottom walls 11 arranged with their apex lowermost as is more clearly illustrated in Fig. 2. Further, tank 10 includes angularly related top walls 12 connected to bottom walls 11, and includes side walls 13.

' Holding the tank 10 in its inclined position are a pair ice the lid 16 is opened so as to retain the lid in such open position.

The work piece to beetched is disposed in the tank 10 above the etchant level. More particularly, the work piece is attached to holder bars 20 by clamps 21, the holder 20 being carried by shaft 22 extending through lid 16. A' gear 23 on shaft 22 engages worm gear 24 provided on the drive shaft of motor 25. A housing 26 is placed overthe motor 25 and gearing 2324 and is secured to the top of lid 16.

Iournalled in bearings 27 between side Walls 13 of the etchant tank, is a paddle shaft 30. A plurality of paddles generally referred to at 31 are attached to shaft 30 in angularly staggered relation. Figs. 3 and 5' illustrate that each paddle 31 is arranged at approximately right angles to each adjacent paddle on the shaft 30.

One end of paddle shaft 30 is provided with a pulley 32connected to a motor pulley 33 by a belt 34. Electric motor 35 is mounted at the rear of the tank 10.

A variable speed transmission is provided by arms 36 pivotally connected to the motor 35, smaller arm 37 being pivoted to arm 36 and attached to pivot plate 40, and handle 41 being attached to pivot plate 40. The belt and pulley assembly and the transmission mechanism are located within the housing provided by side support 14. The handle 41 extends upwardly through one side support 14 for ready manipulation.

Located at the rear of tank 10 is asquirrel cage'fan 42 located .within housing 43. Pipe 44 extends upwardly from housing 43 and extends through the back top wall 12 of tank 10. The pipe 44 places the interior of tank 10 in communication with fan 42.

A trough-like nozzle 45 is attached to the upper end of pipe 44, the nozzle 45 being located Within the tank 10 and extending substantially the entire width of such tank so that the cooling air supplied by fan 42 is delivered over the etchant for substantially the entire width of the tank. 7

The heated air is exhausted from tank 10 through an exhaust port 46 provided in the upper portion of one side wall 13. A chimney pipe 47 is attached to side wall 13 at exhaust port 46 and extends upwardly.

It is seen that the cooling air supplied by fan 42 is delivered downwardly over the etchant by nozzle 46, is heated by the etchant and-is forced outwardly through exhaust port 46. A bafile 49 is provided in pipe 44 to control the flow of air from the fan to the nozzle 45.

Disposed transversely of tank 10 and located at the apex of bottom walls 11 is a tubing 50 that is provided with a plurality of air holes 51, best shown in Fig. 3. The tubing 50 extends outwardly of one side wall 13 and rearwardly for connection to a compressor unit 52.

As will be explained more fully in subsequent descrip tion of parts, the tank 10 is filled with an etchant .to the level indicated by dotted lines in Fig. 3 and referred to i by reference numeral 53. The etchant level 53 is just temperature within the desired limits The front top wall 12 of the tank 10 is provided with I to lid 16 to facilitate opening and closing of the lid, they handles formed to seat on the front top wall 12 when above the lower end of the paddles 31 when disposed in a vertical position. In order for the paddles 31. to operate efiicient and effectively, the etchant level "53 must be raised slightly during operation of the etching machine. For this purpose, the air bubbles emitting from air holes 51 cause a turbulence in the etchant-at the etchant level 53 which has the effect of raising such level. In'addition, aeration of the etchant by theair supplied through tube 50 mixes the etch-ant thoroughly and maintains'the The etchant is introduced into tank 10 through'the inlet valve and tube 54, and is, drained through: valve. and tube 55. i I i The paddles 31 utilized in the etching machine are of Y Bach paddle 31 includes 'a' body portion formed of a I channel member having a flat web plate 56 and side flanges 57. Aligned apertures 58 are provided in side flanges 5 7 closely adjacent the web plate 56, theapertures S'Sreceivingthe paddle shaft 30. Gusset plates 60am attached to the outer surfaces of side flanges 57 and are disposed over the paddle shaft 30, the gu'sset plates 60 serving to connect and maintain adjacent paddles. 31 in right-angular relation.

The ends of web plate '56 are provided with straight transverse margins that serve as etchant-engaging lips 61.

Attached to one side'of 'web plate 56' at one end of paddle 31' is aplate member consisting of a bathe flange 62 extending transversely of' the web plate 56, and an inclined' leading lip. 63 extending transversely of the web plate 56 and inclined. forwardly 'of straight trailing lip 61 in the direction 'ofpaddle rotation to provide a pocket 64 therebetween. It will be noted that when the paddle 31' is disposed in a vertical plane, the outer edges of inclined lip 63 and straight lip 61 lie in the same horizontal plane.

A similar plate member is attached to the other side of web plate 56 at the opposite end of the paddle 31. This plate member includes a baflie flange 65 extending transversely of the web plate '56 in bridging relation to side flanges 57. Further, an inclined leading lip 66 is provided, exten'dingforwardly in the direction of paddle rotation to form a pocket 67 with straight trailing lip 61. Again it will be noted that the outermost edges of lip 66 and lip 61 lie in substantially the same horizontal plane when the paddle is disposed'vertically.

Assuming a clockwise rotation as indicated by the arrows inFig. '5, it wil'l be seen that the inclined lip 63 dips. into and "scoops up a quantity of etchant, such etchant being held by the trough formation formed by baflie flange 62 and inclined lip 63. The etchant scooped up by inclined lip 63 is thrown upwardly against the work piece uponfurther rotation of paddle 31.

Following the movement of inclined lip 63 into the etchant, the straight lip 61 dips into the etchant also and scoops a quantity into the open-end pocket 64. As explained previously, this action is possible since the turbulence in the etchant level caused by aeration has the effect of raising the etchant level behind the inclined lip 63. The etchant carried by pocket 64 is thrown substantially radially outwardly upon the work piece'upon further rotation of. paddles 31. 7

Upon continued rotation of paddle 31, the opposite end of the paddle comes into operative contact with the. etchant. .First, the inclined lip 66 dips into and scoops up a quantity of etchant into the compartment formed by inclined lip 66, baflle flange 65 and the bridging portions of side flanges 57. paddle 31 holds a greater amount of etchant for a longer period of time during rotation than does the pocket formed by flanges 62 and lip 63 at the opposite end of the paddle previously described. Thus, upon continued rotation of paddle 31 the etchant held by lip 66 and flange 65 is deposited at a point higher up on the work piece.

Following the action of inclined lip 66, the straight lip 61 immediately behind dips into and scoops up a quantity of etchant into pocket 67. Again, it is obvious that the etchant in pocket 67 will be held for a greater period of time than the etchant disposed in correspondingpocket 64 at the opposite end of the paddle 31 because at the provision or enclosing side portions formed by side flanges 57.

As explained .lpreviously with respect to lip 61 at the opposite end of paddle 31, the straight. lip 61 partially defining pocket 67 dips into the etchant because the aeration of the etchant has the effect of raising the etchant level immediately behind the inclined lip 66. The etchant held by pocket 67 is thrown radially outwardly and deposited on the work piece upon cont nued rotation of paddle '31,

increase r The particular structure of the paddle, and the eflicient and'effective operation of the component parts in depositing etchant on the work piece provides a complete and uniform etching of the work piece.

In utilizing the etching machine, the work piece is clamped to holder 20 and motor 25 is energized to rotate the work piece when the lid 16 is closed. A predetermined amount of etchant is introduced into the tank 10,-and theaerator is startcd-tOmix-the etchant and cause turbulence at the etchant level. Further, the fan 42 is energized to introduce asupplyct cooling air into the tank compartment abovethe etchant level and to force the heated air outof the exhaust ,port 46. Then,.motor 35, is energized to rotate the paddle shaft and the paddles 31.

Obviously, this structure of the As described previously, the paddles operate to deposit the etchant onto the work piece. After elapse of a predetermined time period suflicient to cause complete etching of the work piece, the motor 33 is deenergized and the rotation of paddles 31' is stopped.

Motor 25 is then deenergized to stop rotation of the Work piece. Then, the lid 16 is opened and the work piece removed from hold'e1f20.

Although the invention has been described by making detailed reference to a single preferred embodiment, and parts thereof, such detail is to be understood in an instructive, rather than in any restrictive sense, many variants being possible within the scope of the claims here unto appended.

I claim as my invention;

1. A paddle forau etchingmachine comprising a body member having means for providing a transverse rotative axis, the body member including a leading lip and a trailing lip atone end, said lips being angularly related to provide an open-end pocket therebctween, said lips extending for substantially the same distance from the said rotative axis so that said trailing lip is adapted to scoop etchantintosaid pocket.

2. The combination "and arrangement of elements as recited above. in claim 1, but further characterized; in that the body member is provided with side flanges between said lips;

3. A paddle for an etching machine comprising a body member, means on said body member for providing a transverse rotative axis medially, the body member including at each end on opposite sides of the rotative axis, a straight trailing lip and leading lip inclined relative to, said trajling lip to provide an open-end pocket therebetween, said lips extending for substantially the sarne distance from said rotative axis so that said trailing lips are adapted to scoop etchant into said pockets.

4. A paddle for an etching machine comprising a body member, means medially on said body member providing a transverse rotative axis, the body member including at each end an outwardly projecting trailing lip and a leading lip inclined relative to said trailing lip to provide an open-end pocket therebetween, said lips extending substantially the same distance from said rotative axis so v that said trailing lips are adapted to scoop etchant into said pockets, at baflie 'flan-ge extending transversely of the body member on each side of the rotative axis, the baffle flange of each end being spaced inwardly from the leading lip, the baflie flange and leading lip at one end being adapted to hold a quantity of etchant, and side flanges on the other end of said body member between the bafilc flange and leading lip to provide a compartment adapted to hold a greater amount of etchant tor a longer period during paddle rotation than the leading lips and baths flange at the opposite end of the body member.

5. In a paddle for an etching machine, a U'-:shaped channel member having a flat plate portion and side flanges, the side flanges. being provided with means medially of the channel member for afiording a transvcrse rota' tive axis, one end of said channel member havinga straight trailing 'lip provided by one end of the plate. por tio'n, "an inclined leading lip attached to one side of the plate portion and arranged at an angle to the straight trailing lip said leading and trailing lips being angularly related to provide an open-end pocket therebetween, said lips extending substantially the same distance from the rotative axis so that said trailing lip is adapted to scoop etchant into said pocket, a baffle flange attached to the same side of the plate portion and extending transversely of the channel member, the baffle flange being spaced inwardly from the inclined leading lip and adapted to cooperate with the inclined leading lip to hold a quantity of etchant, the opposite end of-the channel member having a second straight trailing lip provided by that end of the plate portion, a second inclined leading lip connected to the opposite side of the plate portion, the inclined leading lip extending transversely of the plate portion between the side flanges, the said second inclined leading lip being angularly related to the said second straight trailing lip to provide an end-open pocket between said second leading and trailing lips, and a second baffle flange attached to the plate portion and extending transversely of the channel member between said side flanges, the said second baffle flange being spaced inwardly from the said second inclined leading lip to provide a compartment for holding a greater amount of etchant for a longer period during rotation than the first said leading lip and baifle flange at the opposite end of the plate portion.

6. In an etching machine, an etching tank for holding a supply of etchant, a paddle in said tank, means for rotating said paddle, said paddle including a body member having a straight lip at one end and an angularly related forward lip forwardly of the straight lip in the same plane of rotation and inclined in the direction of paddle rotation to provide an end-open pocket between said lips, the inclined lip being adapted to dip into the etchant and deposit it on the work piece, and an air tube in said tank for agitating the etchant to raise the level so that the following straight lip is adapted to scoop etchant into said pocket.

7. In an etching machine, an etching tank for holding a supply of etchant, a paddle in said tank, said paddle comprising a body member having means medially thereof for providing a transverse rotative axis, each end of said body member being provided with a straight lip, and an angularly related lip disposed in the same plane of rotation with said straight lip and inclined forwardly of the straight lip in the direction of paddle rotation to provide an end-open pocket between said lips, the distance from the rotative axis to the outer end of straight lip being no greater than the distance between the rotative axis and the end of the adjacent respective inclined lip, the inclined lips being adapted to dip into the etchant and deposit on the work piece, and an air tube in said tank for agitating the etchant to raise the level so that the following straight lips are adapted to scoop etchant into said pockets.

8. In an etching machine, an etching tank for holding a supply of etchant, a paddle in said tank, said paddle comprising a U-shaped channel member having a flat plate portion and side flanges, the side flanges being provided with means for afiording a transverse rotative axis, one end of said channel member having a straight lip provided by the end of the plate portion, an inclined lip attached to one side of the plate portion and extending transversely of the channel member, the inclined lip being angularly related to the straight lip and arranged forwardly of the straight li-p in the direction of paddle rotation and in the same plane of rotation to provide an end-open pocket between said lips, the opposite end of said channel member having a second straight lip provided by the opposite end of the plate portion, and a second inclined lip attached to the plate portion in the same plane of rotation with said second straight lip and extending transversely of the channel member between the said side flanges, the second inclined lip being angularly related forwardly of the said second straight lip in the direction of panel rotation to provide an end-open pocket between said second lips, the inclined lip at each end of the channel member being adapted to dip into etchant and deposit it on the work piece, and an air tube in said tank for agitating the etchant to raise the level so that the following straight lips are adapted to scoop etchant into said pockets.

9. A paddle for an etching machine comprising a body member, means medially on said body member providing a transverse rotative axis, the body member including at each end an outwardly projecting trailing lip and a leading lip inclined relative to said trailing lip to provide an open-end pocket therebetween, said leading and trailing lips extending substantially the same distance from said rotative axis so that said trailing lip is adapted to scoop etchant into said pocket, said flanges between the leading and trailing lips at one end of said body member so that the pocket formed thereby is adapted to hold a greater amount of etchant for a longer period of time during rotation than the pocket at the opposite end of the body member, a baflle flange extending transversely of the body member on each side of the rotative axis, the baffle flange of each end being spaced inwardly from the leading lip, the baflle flange and leading lip at one end being adapted to hold a quantity of etchant, and side flanges on the other end of said body member between the baffle flange and leading lip to provide a compartment adapted to hold a greater amount ofetchant for a longer period of time during paddle rotation than the leading lip and baflle flange at the opposite end of the body member.

10. In anetching machine, an etching tank for holding a supply of etchant, a paddle in said tank, means for rotating said paddle, said paddle including a body member having a trailing lip at one end and an angularly related leading lip in the same plane of rotation to provide an end-open pocket between said lips, the leading lip being adapted to dip into the etchant and deposit it on the work piece, and an air tube in said tank for agitating the etchant to raise the level so that the following trailing lip is adapted to scoop etchant into said pocket.

References Cited in the file of this patent UNITED STATES PATENTS 1,576,001 Olden Mar. 9, 1926 1,947,391 Guenst Feb. 13, 1934 2,454,188 Legge r r Nov. 16, 1948 2,523,019 Henderson Sept. 18, 1950 2,651,869 Guenst Sept. 15, 1953 FOREIGN PATENTS 28,011 Holland Oct. 15, 1932 

